Improvement in valves for direct-acting engines



W.` H. McFAUL.

VALVES EOE DIRECT AcTING ENGINE. No.17'8.79Z.

Patented June 13, 1876.

Wmme@ wsNlNGToN o c NITED- STATES PATENT orr'rca.

WILLIAM H. MCFAUL, OF NEW YORK, N. Y.

IMPROVEMENT IN VALVES FRDIRECTFACTING ENGINES.A

Specification forming part of Letters Patent No. 178,792, dated J une 13, 1876; application filed i November 18, 1875.

To all whom it may concern:

Be it known that I, WILLIAM H. MOFAUL, ofthe city, county, and Stat-e ot' New York, have invented certain new and usefull Iniprovements in Valves of Direct-Acting Engines; and I do hereby declare that the fol- `lowing is a full, clear, and exact description ot' the same, reference being had to the accompanying drawing, which forms part of this specification.

This invention more particularly relates to slide-valves of direct-acting engines, using an elongated piston in which there is an exhaustduct between'the heads` of the piston, the same operating in concert with passages in the engine-cylinder or valve-case, which passages are alternately put in communication by the motion ot'gthe piston with said duct, and with opposite endsl ot' the valve-box, to automatically throw the valve by the exhauststeam of the engine. Y

The inwention consists in a novel construction of the valve, including its steam and exhaust passages or cavities, and the fixed passages Which it controls, or by which it is controlled, whereby a balanced or free and most perfect action is obtained for the valve.

Figures 1 and 2 represent longitudinal sections -which, for the purpose of illustration, will here be termed verticalof the cylinder with its piston, and valve oi' a direct-acting engine, constructed in accordance with my invention, said views showing the piston and valve in different working positions. Fig. 3 is a plan or exterior longitudinal view (in a plane at right. angles to the previous iigures) ot' the samewith the valve-box cover removed. Fig. 4 is a side view ofthe valve detached; and Fig. 5 a central transverse section thereof'.

A is the cylinder ot' the engine, and B B its piston, which is an elongated one. O is the and an outer inclosedr D-shaped exhaust-passage, d, interrupted by an outlet, e, in the back ot' the valve, which outlet is in constant communication with the main exhaust-cavity l), which is constructed in the back of the valve box or case F, and always opens to the outlet e in the valve. The steam-cavity c is in uninterrupted communication by diverging passages ff, in either or both sides ofthe valve, with back cavities g g, whereby a counteracting pressure against the live steam acting on the inner D-shaped cavity c is obtained, and a balancing effect or action produced for the valve. The valve E may be reciprocated or worked by mechanical means, as` by an eccentric and valve rod, or it maybe operated automatically through the direct .agency of the steam from the engine-cylinder by the mtion of the engine-piston, which is the arrangement that will here be described. Thus the elongated or double-headed piston B B is made with a cavity, h, which may be annular or not, and extends from head to head of the piston, or nearly so; otherwise this doubleheaded piston may be solid. Passageskk' connect the opposite ends lof the valve-box F with the interior ofthe cylinder A, and with the cavity h, in the piston, alternately during the motion of the piston. Another passage, l, establishes uninterrupted communication between the cavity, It in the piston and the main exhaust.

The operation is as follows: Accordingly as the valve E is thrown to the right or to the lett to bring either of its passages b bin communication with the steam cavity c of the valve, and-the other of said passages with theexhaust-passage d, will the piston B B be worked toward the one end or other of the cylinder A, and accordingly as, during 4such motions of the piston and toward the end of the stroke thereof, either head of the latter uncovers and exposes to the steam in the cylinder either passage lo or kf, While the other of such last-named passagesv has previously been and continues in communication with the exhaust-cavity h of the valve, will the valve E be thrown by the spent steam of the cylinder to the one end or other of the valve-box, and the motion of the piston be reversed as required.

Instead of the cavities and passages D c d d., being for exhaust, and C c c being foi` steam, the cavities and passages D c cl d may be for ste-ani, and G c c for exhaust, in which case the passages ff must connect with the cavity d d., instead of with c c.

The piston-like slide-Valve E, constructed with a steam receiving and distributing facecavity, c, and an outer inclosed exhaust-passage d, havin g` a back outlet, e, in combination with the connterbalancing backsteam-spaces g, the connecting steam-passages f, the back main exhaust D, the face steam-inlet C, and the en gine-passages b b, substantially as shown and described.

WILLIAM H. 'MCFAUL Witnesses MICHAEL RYAN,` BENJAMIN W. HOFFMAN,

FRED. HAYNEs. 

